It is a great idea, as there are two other benefits:
1. Transportation of over large distances has efficiency loss on electricity and requires more cumbersome infrastructure.
2. Less heat on the neighborhood as some of that energy is absorbed into electricity instead of being bounced off to the surrounding. Having normal tiles that just absorb heat will increase the temperature of both the building and the surrounding environment. (requiring even more energy to cool off).
During the summer, NYC, especially manhattan, is famous to have 2F higher temperatures that it normally should have just because of the heat radiation from the building, pavement, and air conditioners.
Requiring a rooftop garden on large buildings is another interesting idea.
> Transportation of over large distances has efficiency loss on electricity and requires more cumbersome infrastructure.
On a rooftop, you have the more significant inefficiencies of trees and suboptimal angles. In a field, you can optimize for efficient collection, and you can even install pivoting panels (much more cheaply than on a house, anyway) which can optimize collection throughout the day.
Even if the transmission loss is larger than the gain from optimal positioning (and I doubt it is), it's all marginal compared to the maintenance difference (having a technician walk out to a panel in a field vs setting up appointments with home residents, driving out to their homes, climbing on their roofs, additional risk of injury for the technician from falls, risk of damaging homes, etc).
No affiliation with this project, but you do know that it is possible to tilt the panels.
(http://www.heliowatcher.com)
>We designed and built a system to automatically orient a solar panel for maximum efficiency, record data, and safely charge batteries. Using a GPS module and magnetometer, the HelioWatcher allows the user to place the system anywhere in the world without any calibration. The HelioWatcher then calculates what the sun’s current location is and orients the panel to the appropriate angle
Yes, I am aware. I mentioned it in the second sentence of my post:
> ... you can even install pivoting panels ...
And like I said in my post, installing these is cheaper and easier in a field than on every home. For one, you only need one "tilt computer" module that can determine the optimal angle for all of the panels in the field. More importantly though, moving parts will wear and break eventually, and it's a lot easier (and safer!) to walk out into the field and service them than scheduling appointments, driving to customers' property, climbing on roofs, etc.
Just for fun, I've built these. You don't even need a GPS module nor magnetometer, you just need a few light sensors, one or two small motors (depending on whether you tilt in one dimension or two), and a couple dollars' worth of standard electronic components.
1. Transportation of over large distances has efficiency loss on electricity and requires more cumbersome infrastructure.
2. Less heat on the neighborhood as some of that energy is absorbed into electricity instead of being bounced off to the surrounding. Having normal tiles that just absorb heat will increase the temperature of both the building and the surrounding environment. (requiring even more energy to cool off).
During the summer, NYC, especially manhattan, is famous to have 2F higher temperatures that it normally should have just because of the heat radiation from the building, pavement, and air conditioners.
Requiring a rooftop garden on large buildings is another interesting idea.